Well I see the loss when I paint on a jpg and then save it back out as a jpg. Colors lose intensity and you can get some minor pixellation.
I'm talking close-ups though, where it's more noticeable.

To answer the question from RobynsVeil I have a quad core oc'd to 3.1 ghz, Win7x64 and 8 Gb RAM. I'm trying NOT to throw the massive texture files at it though, that's the whole point, that I want to use my own jpg's but from files that start out as non-jpg's.

I do understand that most textures undergo alot of editing prior to being released, but that was also part of my main point - I'm looking for the exception to the rule, the highest quality stuff available that hasn't been edited to death already. ;-)

I'm using Modo and Mudbox to paint and to save out the files, not PS. I don't do much painting in PS, maybe a little texture editing here and there, and I use it for working on final image editing, but that's about it. Maybe I should look into PS's jpg export for textures and see if that's better than Modo or Mudbox's.

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